逆向支撑底模反吊在水中防撞墩台施工中的应用

在航道整治工程中设置的桥梁防撞墩,由于墩台的底部经常设置在常年平均水位之下,无法按常规方法采用底部模板正向支撑系统施工。通过采用逆向支撑底模反吊方案,将钢木组合整体模板吊装入水,墩台分层浇筑的方式进行施工。该方案无需设置围堰,形成干地施工条件,成功解决水下混凝土浇筑和模板拆除难的问题,也解决通航水域狭小、操作空间有限、保证正常通航的问题,具有施工方便、安全性高、墩台施工精度易于控制的优点。

Application of reverse supporting system for bottom formwork used in the underwater pier construction

The bottom of the anti-collision bridge pier is placed below the perennial low water level in the waterway regulation work,so it is inapplicable to use conventional forward supporting system for the bottom formwork.We use the construction approach of lifting and placing the steel-wood integrated formwork into water by applying the reverse supporting system,and subsequently casting concrete in layers for the pier.A dry working platform can be created without building a cofferdam.The approach not only successfully solves the difficulties of underwater concrete casting and formwork removal,but also minimizes the execution impact on the normal traffic of vessels in the narrow and limited navigable waters.It is characterized by being easy to perform execution activities,highly safe and easy to control the accuracy of pier construction.